Automatic idler



24, 31967 L. D. HENKE 3,299,868

AUTOMATI C IDLER Filed Sept. 17, 1965 Lowe/l Dean Henke IN IlfN'IOR.

A "army:

United States Patent This application is a continuation-in-part of my prior copending application U.S. Serial No. 306,380, filed September 3, 1963, now abandoned, and pertains to the delayed shutdown of internal combustion engines.

It is well known that proper care and maintenance of heavy duty internal combustion engines calls for idling of the engine before it is completely shutdown. By allowing the engine to idle for a predetermined period under no load conditions, the lubricating fluid and cooling water is given an opportunity to gradually reduce the temperature of the parts and thereby avoid damage that may otherwise occur because of the warping of valves, cracking of cylinder heads and incomplete combustion of fuel producing carbon deposits as well as the seizing of bearings and loosening of oil seals because of extreme heat.

It is therefore a primary object of the present invention to provide a device to be utilized in conjunction with internal combustion engines for automatically setting an idling period durding which the engine may continue to run under no load conditions before complete shutdown.

A further object of the present invention is to provide an engine idler control device through which an optimum idling period may be prescribed and the engine maintained operative during such idling period even though it is turned off in the usual manner.

An additional object of the present invention is to provide a relatively simple and easily installed control device for prescribing an automatic idling period for an internal combustion engine after it is shutdown by the operator in the usual manner.

In accordance with the foregoing objects, the idling control device of the present invention may be simply mounted in any vehicle driven by an internal combustion engine at a suitable location for manipulation by the vehicle operator. Without in any way altering the existing engine shutdown control or ignition switch, the idling control device may be set into operation and the shutdown control opened by the operator when leaving the vehicle. The engine will nevertheless continue to idle thereafter for a predetermined optimum period before there is complete shutdown. 7

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is an electrical circuit diagram showing one form of idle control device in accordance with the present invention,

FIGURE 2 is a rear elevational view of the timing control mechanism associated with the idle control system of the present invention as shown in FIGURE 1.

FIGURE 3 is an electrical circuit diagram showing another form of idle control system in accordance with the present invention.

FIGURE 4 is a transverse sectional view through the interval control mechanism associated with the system shown in FIGURE 3.

FIGURE 5 is a side sectional view taken substantially through a plane indicated by section line 55 in FIG- URE 4 showing a typical installation of the interval control mechanism. e 7

Referring now to the drawings in detail, and initially to FIGURE 1, it will be observed that the idle control system of the present invention will be associated with a source of electrical energy such as a grounded vehicle battery 10. As is well known, a vehicle battery sustains operation of the internal combustion engine. In the case of a Diesel-type of engine, operation of the engine is sustained upon closing a key operated shutdown switch connecting the vehicle battery to a grounded shutdown valve device. In the case of an ignition type of internal combustion engine, the vehicle battery 10 would be connected by conductor 14 and an ignition switch 12 to the ignition coil for engine shut-down purposes. Also connected to the battery by means of conductors 18 and 20, is an interval control mechanism generally referred to by reference numeral 22.

The interval control mechanism as shown in FIGURES l and 2, includes a timer motor 24 one terminal of which may be grounded and the other terminal connected to a switch contact 26. The switch contact is adapted to be selectively engaged by switch arm 28 in order to establish an electrical connection through the switch member 30 and the conductor 18 to the battery 10. The timer motor 24 is thereby energized at the same time that an electrical connection is established through conductor 18 and conductor 20 to the combustion sustaining device or shutdown valve 16 by-passing the key operated switch 12. It will therefore be apparent, that upon displacement of the switch member 30 and switch arm 28 into engagement with the switch contact 26, the battery 10 will maintain the engine operating even after opening of the key operated switch 12 by the operator and at the same time render the interval control mechanism 22 operative by energization of the timer motor 24.

The timer motor is drivingly connected by a reduction gear assembly 32 to a switch actuating cam member 34. The cam 34 is adapted to be manually displaced from its zero position by means of an indicator knob 36 connected thereto as diagrammatically shown in FIGURE 1. Accordingly, the indicator knob 36 will be exposed in any suitable location such as on the vehicle dashboard and cooperate with a scale 38 so that when the operator displaces the knob from its zero position, the timer mechanism may be set to any desired interval. The cam 34 is therefore provided with a notch 40 adapted to receive a switch actuator element 42 so that only when the cam 34 is in its zero position as indicated by the knob 36, will the switch contact 26 be opened.

The utility and operation of the idling control device will be apparent from the foregoing description. The operator may set the interval control mechanism 22 to a predetermined idling period by angular displacement of the knob 36 from the zero position. An energizing circuit is then established for both the timer motor 24 and the combustion sustaining device 16 in by-pass relation to the key operated switch 12 opened by the operator upon leaving the vehicle. The timer motor 24 will then slowly return the cam 34 to its zero position at which time the circuits are opened in order to complete shutdown of the engine. The engine will therefore idle during the preset period for reasons hereinbefore indicated without requiring the attention of the operator.

Referring now to FIGURE 3, another form of idle control system is shown associated for example with a grounded vehicle battery 44 adapted to be electrically connected by the key operated ignition switch 46 to the grounded ignition coil 48 associated with an ignition type of internal combustion engine. A conductor 50 connects the battery to one terminal 52 of an interval control device 54, the other terminal 56 thereof being electrically connected through-the selectively actuated push button switch 58 to the ignition coil 48. Accordingly, upon closing of the push button switch 58 by the operator, the interval control device 54 will establish an energizing circuit for the ignition coil 48 'by-passing the ignition switch 46 in order to maintain the engine idling for a predetermined idle period after the ignition switch 4-8 is opened. Thus, the vehicle operator may open the ingition switch 46 upon leaving the vehicle and yet maintain the engine idling for an optimum period by merely closing the push button switch 58. At the end of the idling period the engine will be completely shutdown without requiring any further attention on the part of the vehicle operator.

Referring now to FIGURES 4 and 5, it will be observed that the interval control device 54 includes a nonconductive casing 60 from which the terminals 52 and 56 project. The casing includes an axially projecting portion 62 which is externally threaded at 64 so as to be received within a threaded opening formed in the water cooling jacket 66 associated with the internal combustion engine. Projecting from the casing into the water or coolant 68, is a probe member 70. The probe member establishes an electrical connection at its inner end within the casing, between the radially inner end of a spiral heat sensing element 72 and the terminal 2. The radially outer end portion 74 of the heat sensing element mounts a contact 76 adapted to engage a contact on a magnetic retarding member 78 electrically connected to the terminal 56. It will therefore become apparent, that when the temperature of the cooling water 68 rises for example above 170 F., the heat conducted therefrom through the probe member 70 to the spiral sensing element 72 will cause its radially outer end to engage the contact 76 with the contact on the magnetic element 78 in order to establish an electrical connection between the terminals 52 and 56. Therefore, after the engine has been operating for a substantial length of time, closing of the switch push button switch 58 will establish and energizing circuit for the ignition coil 48 in order to maintain the engine idling even after the ignition switch 46 is opened. The cooling water 68 will then decline in temperature 'below 170 F., but because of the magnetic element, not until the temperature has decreased to 160 F. will the contracting force of the sensing element 72 be sufiicient to open the contacts and thereby interrupt the energizing circuit for the ignition coil 48. The idling internal will therefore be determined by the temperature of the cooling water.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. In combination with an internal combustion engine having electrically operated combustion sustaining means, a source of electrical energy and a shutdown switch connecting the source to the electrically operated means, an idle control mechanism comprising, interval control means connected to said source of electrical energy in parallel with said switch for maintaining the electrically operated means energized upon opening of the switch, and selective- 1y operated means connecting the electrically operated means to the interval control means for rendering the same operative during a predetermined idle period initiated by said opening of the switch to permit gradual cooling of the engine while running under no load conditions.

2. The combination of claim 1 wherein said interval control means comprises, a timer motor, reduction gear means drivingly connecting the motor to the selectively operated means for movement thereof from a preset position to a zero position, and cam operated switch means closed in response to displacement of the selectively operated means from the zero position for connecting the source of electrical energy to the motor and the electric-ally operated means.

3. The combination of claim 2 wherein said electrically operated means is an ignition coil of an ignition type internal combustion engine.

4. In combination with an internal combustion engine having electrically operated combustion sustaining means, a source of electrical energy and a shutdown switch connecting the source to the electrically operated means, an idle control mechanism comprising, interval control means connected to said source of electrical energy in parallel with said switch for energizing the electrically operated means after opening of the switch, and selectively operated means connecting the electrically operated means to the interval control means for rendering the same operative for a predetermined idle period, said interval control means comprising, a casing adapted to be secured to the internal combustion engine, a heat sensing element enclosed within the casing, probe means connected to the sensing element and projecting from the casing into the engine, contact means actuated by the sensing element for electrically connecting the source of electrical energy to the selectively operated means in response to elevation of the probe means in temperature to one value, and magnetic means for delaying opening of the contact means in response to a decline in temperature below said one value.

5. The combination of claim 4 wherein said selectively operated means is a push button switch connecting said contact means to the electrically operated means.

6. The combination of claim 5 wherein said internal combustion engine includes a water cooling jacket into which said probe means projects.

7. The combination of claim 6 wherein said electrically operated means is an ignition coil.

8. In combination with an internal combustion engine having cooling means, combustion sustaining means and a source of electrical energy connected to said combustion sustaining means by an engine shutdown switch, means for delaying shut down of the engine upon opening of the shutdown switch comprising, interval control means connected to said source in parallel with the shutdown switch for establishing an engine cooling period during which said cooling means declines in temperature from the temperature at the instant the shutdown switch is opened, means connecting the interval control means to the combustion sustaining means for maintaining the engine idling during said cooling period to reduce the rate at which the cooling means declines in temperature, said interval control means including deenergizing means for electrically diconnecting the source from the combustion sustaining means to terminate said cooling period.

-9. The combination of claim 8 wherein said interval control means further includes a timer motor connected to the source by the switch means and switch actuating means operated by said motor for actuating the denergizing means and opening the switch means at the end of said cooling period to simultaneously disconnect the source from the motor and the combustion sustaining means.

References Cited by the Examiner UNITED STATES PATENTS 1,219,646 3/ 1917 Kyburg. 2,434,871 1/1948 Taft 123198 2,565,984 8/1951 Newman et al. 123198 X 2,861,558 11/1958 McClain 123-10-2 3,241,539 3/1966 Kuehn 123-198 FOREIGN PATENTS 534,729 12/ 1956 Canada.

MARK NEWMAN, Primary Examiner.

AL LAWRENCE SMITH, Examiner. 

1. IN COMBINATION WITH AN INTERNAL COMBUSTION ENGINE HAVING ELECTRICALLY OPERATED COMBUSTION SUSTAINING MEANS, A SOURCE OF ELECTRICAL ENERGY AND A SHUTDOWN SWITCH CONNECTING THE SOURCE TO THE ELECTRICALLY OPERATED MEANS, AN IDLE CONTROL MECHANISM COMPRISING, INTERVAL CONTROL MEANS CONNECTED TO SAID SOURCE OF ELECTRICAL ENERGY IN PARALLEL WITH SAID SWITCH FOR MAINTAINING THE ELECTRICALLY OPERATED MEANS ENERGIZED UPON OPENING OF THE SWITCH, AND SELECTIVELY OPERATED MEANS CONNECTING THE ELECTRICALLY OPERATED MEANS TO THE INTERVAL CONTROL MEANS FOR RENDERING THE SAME OPERATIVE DURING A PREDETERMINED IDLE PERIOD INITIATED BY SAID OPENING OF THE SWITCH TO PERMIT GRADUAL COOLING OF THE ENGINE WHILE RUNNING UNDER NO LOAD CONDITIONS. 